Ovary and egg fatty acid composition of greater amberjack broodstock (Seriola dumerili) fed different dietary fatty acids profiles

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An overview of the reproductive cycle of cultured specimens of a potential candidate for Mediterranean aquaculture, Umbrina cirrosa

The shi drum (Umbrina cirrosa), belonging to the Sciaenidae family of fish (Nelson et al., 2016) has attracted attention as it is an excellent diversification species in Mediterranean aquaculture to combat the low prices of the most cultured species due to the appearance of new producing countries in the Mediterranean area. In this manuscript we describe for the first time the reproductive cycle of captive shi drum specimens that are able to spontaneously spawn in captivity. Our data show that spermatogenesis started in one year old shi drum spe- cimens, although the fish were not mature enough to complete the reproductive cycle. Thus, three year old specimens showed multiple spawns with around 65% of the eggs fertilized. In mature males, levels of 11-ke- totestosterone (11KT), testosterone (T) and progesterone (P) were detected in serum and gonad, while 17β- estradiol (E2) was only detected in gonad. Testicular levels of E2 and P suggest that these hormones might have a role in spawning and in the subsequent spermatogonial proliferation. In mature females, however, P and E2 were detected in serum and gonad, while T and 11KT were only detected in gonad. The pattern shown by P in the ovary indicates a link between this hormone and ovarian renewal and a delay in vitellogenesis, which would explain why the vitellogenic stage of shi drum is quite short. The level of T and 11KT in the ovary suggests a role in oocyte maturation and spawning. The differences observed between sexes in the prevalence of some infection and the important economic losses produced by some vertically transmitted pathogens; have increase the at- tention to the interactions between the immune and reproductive systems. In this study we observed differences between sexes in the protease and bactericide activity levels. Thus, this manuscript represents the most complete overview to date of the shi drum reproductive cycle.Versión del editor2,04

Democratic Politics in Times of Austerity: The Limits of Forced Reform in Greece

F ew people have been shielded from the recentfinancial crisis and fewer still have suffered morethan the Greeks. With unemployment rates above 27 percent, youth unemployment just below 60 percent, 25 percent shrinking of the GDP since 2009, higher taxes, lower wages and pensions, and only modest price deflation in the market, it is hard to be optimistic about a quick economic recovery. From Stagnation to Forced Adjustment provides a thorough discussion of the chronic pathologies that rendered Greece the weakest link during the Eurozone crisis. The book’s contributors consider a range of explanations for “reform stagnation ” in Greece despite the presence of seemingly favorable institutional conditions since the transition to democ-racy in 1974—a unitary state with stable one-party governments, cohesive parties, and few veto players. The theme of the volume is that lack of reform i

Interstate Relations, Perceptions, and Power Balance: Explaining China’s Policies toward Ethnic Groups, 1949-1965

Why do multi-ethnic states treat various ethnic groups differently? How do ethnic groups respond to these state policies? We argue that interstate relations and ethnic group perceptions about the relative strength of competing states are important—but neglected—factors in accounting for the variation in state-ethnic group relations. In particular, whether an ethnic group is perceived as having an external patron matters a great deal for the host state's treatment of the group. If the external patron of the ethnic group is an enemy of the host state, then repression is likely. If it is an ally, then accommodation ensues. Given the existence of an external patron, an ethnic group's response to a host state's policies depends on the perceptions about the relative strength of the external patron vis-à-vis the host state and whether the support is originating from an enemy or an ally of the host state. We present five configurations and illustrate our theoretical framework on the eighteen largest ethnic groups in China from 1949 to 1965, tracing the Chinese government's policies toward these groups, and examine how each group responded to these various nation-building policies

Exchange on the quantitative measurement of ethnic and national identity

In recent decades, there has been a noticeable increase in the use of quantitative techniques in the study of ethnicity and nationalism, without, however, a sufficient amount of reflection on how these techniques have contributed to our understanding of ethnic and national identities. As such, in this exchange three sets of authors answer questions about the degree to which it is possible to use quantitative data to measure ethnic and national identities, which types of methods are most suitable in measuring these identities and what the major research findings of this quantitative research are that were not possible using qualitative approaches